1. Field of the Invention
The invention relates to an energy harvesting system, more particularly to a solar-powered energy harvesting system.
2. Description of the Related Art
Fossil fuel, gasoline and natural gas are among the most commonly used energy sources. However, they are sources of environmental hazards that pose threats to the environment. With the decrease of the available amount of these energy sources and with the increase of environmental consciousness, non-polluting and viable energy, such as solar energy, is developing into a major alternative energy source.
A conventional solar-powered energy harvesting system includes at least one solar panel and a control circuit. In order to achieve the greatest harvesting efficiency possible, separate measuring equipment is required to obtain a set of parameters in current and voltage corresponding to the energy generated by the solar panel under different loading conditions. The set of parameters are loaded into the control circuit via firmware, and are used for locating a maximum power point for optimal operation of the solar panel.
However, the conventional solar-powered energy harvesting system has the following limitations:
1. Additional measuring equipment is required for generating the set of parameters, creating additional costs.
2. Once the set of parameters are loaded into the control circuit, they cannot be changed. However, characteristics of the solar panel may vary according to weather conditions and ambient temperature. Therefore, it is likely that the solar panel does not actually operate at the maximum power point.
3. The set of parameters loaded into the control circuit corresponds to the specific solar panel from which it is measured, such that the control circuit is designed for controlling that specific solar panel only. Therefore, the conventional solar-powered energy harvesting system is not flexible in that once the solar panel is replaced, the control circuit needs to be updated with a new set of parameters that correspond to the replacement solar panel, resulting in extra costs.